package com.cskaoyan.order.biz.handler;

import com.alibaba.fastjson.JSON;
import com.cskaoyan.mall.commons.exception.BaseBusinessException;
import com.cskaoyan.mall.commons.exception.BizException;
import com.cskaoyan.order.biz.context.CreateOrderContext;
import com.cskaoyan.order.biz.context.TransHandlerContext;
import com.cskaoyan.order.dal.entitys.Stock;
import com.cskaoyan.order.dal.persistence.StockMapper;
import com.cskaoyan.order.dto.CartProductDto;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;

import java.util.LinkedList;
import java.util.List;
import java.util.Optional;
import java.util.stream.Collectors;

/**
 * @Description: 扣减库存处理器
 **/
@Component
@Slf4j
public class SubStockHandler extends AbstractTransHandler {

    @Autowired
    StockMapper stockMapper;

    @Override
    public boolean isAsync() {
        return false;
    }

    @Override
    @Transactional
    public boolean handle(TransHandlerContext context) {
        CreateOrderContext createOrderContext = (CreateOrderContext) context;

        List<CartProductDto> dtoList = createOrderContext.getCartProductDtoList();

        LinkedList<Long> longs = new LinkedList<>();
        createOrderContext.setBuyProductIds(longs);
        List<Long> productIds = createOrderContext.getBuyProductIds();

        if (CollectionUtils.isEmpty(productIds)) {
            for (CartProductDto cartProductDto : dtoList) {
                productIds.add(cartProductDto.getProductId());
            }
            productIds.sort(Long::compareTo);
        }
        // 锁定库存
        List<Stock> stocksForUpdate = stockMapper.findStocksForUpdate(productIds);

        if (CollectionUtils.isEmpty(stocksForUpdate)) {
            throw new BizException("库存未初始化");
        }

        if (stocksForUpdate.size() != productIds.size()) {
            throw new BizException("部分商品库存未初始化");
        }

        // 扣减库存
        for (CartProductDto cartProductDto : dtoList) {
            Long productId = cartProductDto.getProductId();
            Long productNum = cartProductDto.getProductNum();

            Stock target = stockMapper.selectStock(productId);
            if (productNum > target.getRestrictCount()) {
                throw new BizException("超出限购数量");
            }
            if(productNum>target.getStockCount()){
                throw new BizException("库存不足");
            }
            Stock stock = new Stock();
            stock.setItemId(productId);
            stock.setLockCount(productNum.intValue());
            stock.setStockCount(-productNum);

            stockMapper.updateStock(stock);
        }
        return true;
    }
}